Parasitism : organic and social / by Jean Massart and Émile Vandervelde ; translated by William Macdonald ; revised by J. Arthur Thomson.

  • Massart, Jean, 1865-1925.
Date:
1895
Catalogue details

Licence: Public Domain Mark

Credit: Parasitism : organic and social / by Jean Massart and Émile Vandervelde ; translated by William Macdonald ; revised by J. Arthur Thomson. Source: Wellcome Collection.

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    sphere the cai'bon which they hâve derived from the plants, and give back to the soil the minerai éléments which the plants had, for the time, brought witbin the circle of life. Among the more characteristic forms of animal and plant life, the modes of nutrition are specialised, and do not show that astonishing diversity which we find among Infusorians. Thus the seed-bearing plants or Pbanerogams are almost exclusively holophytic, and the backboned animais or Vertebrates are, with few exceptions, predatory. Similarly, most of the mush- room-like Fungi (Basidiomycetes) are saprophytes, and the tape-worms or Cestodes are wholly parasitic. Among these different modes of nutrition, the holophytic method is evidently the most primitive. For one cannot conceive that the first living créatures which appeared on the earth can hâve fed on any- thing but inorganic matter.1 The primitive holophytic organisais must hâve been followed by those which were able to feed upon organic débris, and to reduce that once more to in- organic material. The occurrence of saprophytes is essential to the conservation of life. If the sapro- phytic, coprophagous, and necrophagous organisais 1 [It is at least conceivable that they fed on organic compounds which did not achieve vitality. See Ray Lankester’s article, Protozoa, “Encyclop. Britannica.”—Tr.]